Door With Labyrinth Feature

ABSTRACT

A temperature-controlled enclosure for displaying cold items. The enclosure includes a body having a front opening and defining an interior space. A frame assembly is coupled in the front opening. One or more doors are coupled to the frame assembly. At least one of the doors includes one or more window panels, a housing assembly that holds the window panels, and a gasket. A ridge projects from the rear surface of the housing assembly between the gasket and the interior space of the enclosure. The ridge extends across a portion of an air gap between the rear surface of the housing assembly and a front surface of the frame assembly.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of Indian Application No. 202141022785, filed on May 21, 2021, and entitled “Door with Labyrinth Feature,” the entire contents of which is incorporated by reference herein.

TECHNICAL FIELD

This invention relates to temperature controlled storage devices, and doors and associated frames used in such devices.

BACKGROUND

Refrigerated enclosures are used in commercial, institutional, and residential applications for storing and/or displaying refrigerated or frozen objects. Refrigerated enclosures may be maintained at temperatures above freezing (e.g., a refrigerator) or at temperatures below freezing (e.g., a freezer). Refrigerated enclosures have one or more doors or windows for accessing and viewing refrigerated or frozen objects within a temperature-controlled space. Refrigerated enclosures typically include a frame that supports the doors or windows.

Condensation on sealing surfaces of doors of refrigerated enclosures and their associated frames can impair sealing and decrease energy efficiency. Formation of condensation (or frost formation) on a door also affects visibility to product placed inside enclosure and may cause customer dissatisfaction. Electric heater wires are sometimes employed in the thermal frames of commercial refrigerated enclosures to inhibit condensation. However, electrical heaters can use a significant amount of electrical power. Excess reliance on such heater wires may make ever more stringent government regulations on energy efficiency more difficult to meet.

SUMMARY

In some implementations, a labyrinth feature is provided between a door and an associated frame of a refrigerated enclosure. The labyrinth feature may improve thermal performance of door (e.g., better U value of cross section) and help reduce air leakage around the edges of the door. Because of improved thermal performance, the door may need less heater power to avoid external condensation on door, which also helps to reduce energy consumption of door.

One aspect of the invention features a temperature-controlled enclosure for displaying cold items. The enclosure includes a body having a front opening and defining an interior space. A frame assembly is coupled in the front opening. One or more doors are coupled to the frame assembly. Each of the doors includes one or more window panels, a housing assembly that holds the window panel(s), and a gasket. The gasket is coupled to the housing assembly on the rear surface of the housing assembly along the perimeter and forms a seal between the frame assembly and the door when the door is closed. A ridge projects from the rear surface of the housing assembly between the gasket and the interior space of the enclosure. The ridge extends across a portion of an air gap between the rear surface of the housing assembly and a front surface of the frame assembly.

In some implementations, the ridge defines an air passage between the interior space and the gasket when the door is closed. The ridge inhibits air flow between the gasket and the interior space of the enclosure.

In some implementations, the ridge defines a labyrinthine air passage between the interior space of the enclosure and an inner surface of the gasket when the door is closed. The labyrinthine air passage can include a first segment between the ridge and a front surface of the frame assembly, and a second segment between an outer surface of the ridge and an inner surface of the gasket. The labyrinthine air passage inhibits air leakage between the gasket and a contact plate of the frame assembly.

In some implementations, the labyrinthine air passage is configured to inhibit air leakage between the gasket and a contact plate of the frame assembly.

In some implementations, the labyrinthine air passage is configured to inhibit heat transfer between ambient air around the temperature-controlled storage device and the interior space of the enclosure.

In some implementations, a labyrinthine air passage inhibits condensation on the door or the frame assembly.

In some implementations, a ridge is formed in a window panel retaining member.

The ridge is formed in the window panel retaining member.

In some implementations, a ridge includes a flexible material.

In some implementations, a ridge includes a rigid material.

In some implementations, the ridge includes a hollow core.

In some implementations, the ridge includes, in cross section, a rectangular shape.

In some implementations, the ridge includes, in cross section, a polygonal shape.

In some implementations, the ridge includes at least one rounded external surface.

In some implementations, the air gap between the ridge and the front surface of the frame assembly is about 3 millimeters or less.

In some implementations, the temperature-controlled enclosure includes one or more additional ridges projecting from the rear surface of the housing assembly. At least one of the additional ridges at least partially defines the air passage between the interior space and the gasket when the door is closed. The at least one additional ridge is configured to inhibit air flow between the gasket and the interior space of the enclosure.

In some implementations, a ridge runs along the gasket around the perimeter of the housing assembly.

In some implementations, at least a portion of the ridge runs along the gasket on the top edge or the bottom edge of the door.

In some implementations, at least a portion of the ridge runs along the gasket on at least one of the side edges of the door.

In some implementations, at least a portion of the ridge runs along the gasket on a hinged side of the door.

In some implementations, at least a portion of the ridge runs along the gasket on a handle side of the door.

In some implementations, at least a portion of the ridge is between the gasket and an exposed edge of at least one of the window panels.

In some implementations, a ridge extends across a portion of an air gap between the rear surface of the housing assembly and a front surface of a mullion.

In some implementations, the frame assembly includes a contact plate. At least one segment of an air passage between the gasket and the interior space is at least partially defined by a gap between the ridge and a front surface of the contact plate.

In some implementations, the frame assembly includes a main frame member and a backing member coupled to the main frame member, wherein the backing member comprises a leg on the inner side of the main frame member. At least one segment of an air passage between the gasket and the interior space is at least partially defined by a gap between the ridge and a front surface of the leg of the backing member.

Another aspect of the invention features a temperature-controlled enclosure for displaying cold items. A ridge extends across a portion of an air gap between a rear surface of the housing assembly and a front surface of a frame assembly. The ridge inhibits air flow between the gasket and the interior space of the enclosure. In some implementations, the ridge extends from the rear surface of the door and toward the front surface of the frame assembly. In other implementations, the ridge extends from the front surface of the frame assembly and toward a rear surface of the door.

In some implementations, the ridge projects from the rear surface of the housing assembly between the gasket and the interior space of the enclosure.

In some implementations, the ridge projects from the front surface of the frame assembly between the gasket and the interior space of the enclosure.

Another aspect of the invention features a door for a temperature controlled enclosure for displaying cold items. The door includes one or more window panels, a housing assembly, a gasket, and a ridge. The housing assembly is configured to hold the one or more window panels along the exterior edges of the one or more window panels. The housing assembly includes a rear surface and defining a perimeter. The gasket is coupled to the housing assembly on the rear surface of the housing assembly along the perimeter. The gasket is configured to form a seal between the frame assembly and the door when the door is closed. The ridge projects from the rear surface of the housing assembly interior to the gasket. When the door is closed on a frame assembly mounted in an enclosure of the temperature controlled storage device, the ridge is configured to extend across at least a portion of an air gap between the rear surface of the housing assembly and a front surface of the frame assembly.

Another aspect of the invention features a method of improving thermal performance of a refrigerated enclosure. The method includes providing a frame assembly for holding a door for the refrigerated enclosure, and providing a ridge on a rear surface of a door of the enclosure interior to a gasket of the door. When the frame assembly and door are installed and the door is closed, a labyrinthine air passage is created between the door and the frame assembly. The labyrinthine air passage is defined by the ridge. The ridge inhibits air flow between the gasket and the interior space of the enclosure. This helps improve overall U value of the cross-section.

The concepts described herein may provide several advantages. For example, implementations of the invention may provide a frame with improved thermal efficiency. Implementations may prevent or minimize condensation build up on door sealing surfaces. Implementations may provide for a more positive thermal seal between a thermal frame and a door.

The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.

DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view of a refrigerated enclosure having multiple doors supported by a frame.

FIG. 2 is a perspective view of a refrigerated enclosure having a single door supported by a frame.

FIG. 3 is a cross-sectional view showing an example refrigerated enclosure with two doors and a mullion according to implementations of the present disclosure.

FIG. 4 is perspective cross sectional view of a door including a ridge projecting from a rear surface according to implementations of the present disclosure.

FIG. 5 is perspective cross sectional view of housing assembly of a door that includes according to implementations of the present disclosure.

FIG. 6 is a cross sectional view of housing assembly of a door that includes according to implementations of the present disclosure.

FIG. 7 is cross sectional view an interface between a door and a frame assembly for the door according to implementations of the present disclosure.

FIG. 8 is a detail view illustrating a ridge that projects from a rear surface of a door.

FIG. 9 is a vertical cross-sectional view showing an example refrigerated enclosure with ridges on top and bottom door perimeter segments according to implementations of the present disclosure.

FIG. 10 is an example of a ridge having a square cross section with a hollow core.

FIG. 11 is an example of a ridge having a thin rectangular solid cross section.

FIG. 12 is an example of a ridge having a rounded hollow cross section.

FIG. 13 is an example of a ridge having a triangular hollow cross section.

FIG. 14 illustrates a rear retaining member that includes a ridge.

FIG. 15 illustrates a ridge in the form of a removable strip.

FIG. 16 illustrates a frame assembly having a ridge that partially extends across an air gap to a door.

FIG. 17 illustrates a frame segment assembly according to an illustrative implementation.

FIG. 18 shows a thermal map of results from thermal modeling performed on a door and frame segment assembly.

Like reference symbols in the various drawings indicate like elements.

DETAILED DESCRIPTION

In some implementations, a labyrinthine air passage is provided near the interface of a door housing, gasket, and frame. A projecting element on the inside of the door near the gasket helps to reduce velocity of air entering in that cross section. A reduced air velocity near the gasket helps to improve thermal performance, as well as to reduce air leaks through gasket.

FIGS. 1-2 show an exemplary refrigerated enclosure 10. Refrigerated enclosure 10 may be a refrigerator, freezer, or other enclosure defining a temperature-controlled space. In some implementations, refrigerated enclosure 10 is a refrigerated display case. For example, refrigerated enclosure 10 may be a refrigerated display case or refrigerated merchandiser in grocery stores, supermarkets, convenience stores, florist shops, and/or other commercial settings to store and display temperature-sensitive consumer goods (e.g., food products and the like). Refrigerated enclosure 10 can be used to display products that must be stored at relatively low temperatures and can include shelves, glass doors, and/or glass walls to permit viewing of the products supported by the shelves. In some implementations, refrigerated enclosure 10 is a refrigerated storage unit used, for example, in warehouses, restaurants, and lounges. Refrigerated enclosure 10 can be a free standing unit or “built in” unit that forms a part of the building in which refrigerated enclosure 10 is located.

Refrigerated enclosure 10 includes a body 12. Body 12 includes a top wall 14, a bottom wall 16, a left side wall 18, a right side wall 20, a rear wall (not shown), and a front portion 22 defining a temperature-controlled space. Front portion 22 includes an opening into the temperature-controlled space. Thermal frame 24 is can be mounted at least partially within the opening. Thermal frame 24 includes a plurality of perimeter frame segments (i.e., a header or top frame segment 26, a sill or bottom frame segment 28, a left side frame segment 30, and a right side frame segment 32) forming a closed shape along a perimeter of the opening. In some implementations, thermal frame 24 includes one or more mullion frame segments 34 dividing the opening into multiple smaller openings. For example, FIG. 1 illustrates a three-door assembly with a pair of mullion frame segments 34 extending between top frame segment 26 and bottom frame segment 28 to divide the opening into three smaller openings. Each of the smaller openings may correspond to a separate door 36 of the three-door assembly. In other implementations, mullion frame segments 34 may be omitted. For example, FIG. 2 illustrates a one-door assembly wherein thermal frame 24 includes perimeter frame segments 26-32 but not mullion frame segments 34. In some implementations, thermal frame 24 includes include top frame segment 26 and bottom frame segment 28 with no side frame segments 30 or 32. In such implementations, thermal frame 24 may include one or more mullion frame segments (e.g., such as mullion 34 frame segment 34 shown in FIG. 1) depending, for example, on the size of the refrigerated enclosure in which thermal frame 24 is to be installed and the number of doors.

Refrigerated enclosure 10 includes one or more doors 36 pivotally mounted on the thermal frame 24 by hinges 38. In some implementations, the doors 36 are sliding doors configured to open and close by sliding relative to the thermal frame 24. The example doors 36 illustrated in FIGS. 1 and 2 include panel assemblies 40 and handles 42. Referring to FIG. 2, thermal frame 24 is includes a series of contact plates 44. Contact plates 44 are be attached to a front surface of thermal frame 24 and provide a sealing surface against which doors 36 rest in the closed position. For example, doors 36 may include a gasket or other sealing feature around a perimeter of each door 36. The gaskets may employ a flexible bellows and magnet arrangement, which, when the doors 36 are closed, engage contact plates 44 to provide a seal between doors 36 and thermal frame 24. The thermal frames provide a thermally conductive path from the frame segments 26-32, for maintaining maintains the temperature of the contact plates 44 at or close to the temperature of the external environment (e.g., the environment outside of the refrigerated enclosure 10) and to aid in preventing condensation from forming on the contact plates 44. Preventing condensation on the contact plates may provide for a more positive seal between the contact plates 44 and a magnetic gasket on the door, thereby improving the thermal properties of the refrigerated enclosure 10.

FIG. 3 illustrates a cross-sectional view of the refrigerated enclosure 10 taken along the line 3-3 in FIG. 1. FIG. 3 illustrates the pair of side walls 18 and 20 of the refrigerated enclosure 10 extending rearward from front portion 22, and a rear wall 46 extending between side walls 18 and 20 to define a temperature-controlled space 48 within the body 12.

In FIG. 3, refrigerated enclosure 10 is shown as a two-door assembly with a pair of doors 36 positioned in an opening in front portion 22. Refrigerated enclosure 10 may have two doors 36 (as shown in FIG. 3), a lesser number of doors 36 (e.g., a single door as shown in FIG. 2), or a greater number of doors 36 (e.g., three or more doors as shown in FIG. 1). Each door 36 includes a panel assembly 40 and a handle 42. Applying a force to handle 42 causes the corresponding door 36 to rotate about hinges 38 between an open position and a closed position. In some implementations, panel assembly 40 is a transparent or translucent panel assembly through which items within temperature-controlled space 48 can be viewed when doors 36 are in the closed position. For example, panel assembly 40 is shown to include a plurality of transparent or translucent panels 50 with spaces 52 there between. The spaces 52 can be sealed and filled with an insulating gas (e.g., argon) or evacuated to produce a vacuum between panels 50. In some embodiments, panel assembly 40 includes opaque panels with an insulating foam or other insulator there between. Doors 36 include gaskets 54 attached to a rear surface of doors 36 along an outer perimeter of each door. Gaskets 54 are configured to engage a sealing surface of the contact plates 44 a and 44 b (referred to collectively as contact plates 44) when the doors 36 are in the closed position, and to thereby provide a seal between doors 36 and contact plates 44.

The perimeter frame segments 30-32 of the thermal frame 24 are coupled to the body 12 of the refrigerated enclosure 10 by mounting brackets 68. Mounting brackets 68 can be secured to perimeter frame segments 30-32 using one or more connection features (e.g., flanges, notches, grooves, collars, lips, etc.) or fasteners (e.g., bolts, screws, clips, etc.) and may hold perimeter frame segments 30-32 in a fixed position relative to the body 12 of the refrigerated enclosure 10.

Although only two perimeter frame segments 30-32 are shown in FIG. 3, other perimeter frame segments (e.g., header/top frame segment 26 and sill/bottom frame segment 28) may be configured in a similar manner. For example, a top frame segment and a bottom frame segment may be coupled to the body 12 of the refrigerated enclosure 10 by mounting brackets 68.

The perimeter frame segment assembly includes a perimeter frame segment (i.e., one of frame segments 26-32 shown in FIGS. 1 and 2), a mounting bracket 68, and a contact plate 44.

One or more mullion frame segments 34 extend vertically between top frame segment 26 and bottom frame segment 28. A top portion of mullion frame segment 34 is fastened to a top frame segment 26 and a bottom portion of mullion frame segment 34 is fastened to a bottom frame segment 28.

In some implementations, a labyrinthine air passage is at least partially defined by a projecting ridge that runs along the door gasket interior to (on the cold-side of) the gasket for the door of a refrigerated enclosure. The ridge can be in the form of a rail, a bar, a plate, or other elongated element. The ridge can extend part way across an air gap between the inside face of the door and the front surface of the frame in which the door is installed. The ridge and the labyrinthine air passage may serve as a thermal barrier between the cold interior space of the enclosure and the warmer ambient outside of the enclosure.

FIG. 4 illustrates a door including a ridge that can be used to form a labyrinthine air passage between a gasket and the interior space of a refrigerated enclosure.

For illustrative purposes, only a corner of the door is shown. Nevertheless, the cross section shown in FIG. 4 can continue around the entire perimeter 45 of window panel assemblies 40.

Door 36 includes window panel assembly 40 and gasket 54. Window panel assembly 40 includes panels 50 and housing assembly 100. Housing assembly 100 surrounds and supports the edges of window panels 50.

Gasket 54 may run continuously around the perimeter of door 36. In various implementations, gasket 54 can be a single continuous piece, or can include a set of gasket components, with one gasket component on each of the edges of the perimeter. Gasket 54 can be made of a resilient material, such as synthetic rubber.

Housing assembly 100 includes outer housing member 102 and rear retaining member 104. Rear retaining member 104 can snap together with outer housing member 106 by way of complementary engaging portions 106, 108. Window panels 50 are stacked between front retaining rim 110 of outer housing member 106 and rear retaining rim 112 of rear retaining member 104.

Rear retaining member 104 includes ridge 114. Ridge 114 extends in a rearward direction from a rear surface of door 36 on the interior side of gasket 54. Ridge 114 may continue around the perimeter of door 36. Thus, a section of ridge 114 may include a segment that runs along each of the edges (top, bottom, left side, and right side) of door 36 interior to corresponding segments of gasket 54.

In the example shown in FIG. 4, adjoining segments of ridge 114 meet at miter joint 118, such that the adjoining segments of ridge 114 meet and contact one another at the corners of door 36.

Referring to FIG. 5, ridge 114 includes crown 120, inner wall 122, and outer wall 124. A hollow core 126 of ridge 114 is defined by the surrounding walls. As will be further described below, ridge 114 can be, in various implementations, rigid or flexible.

Referring to FIG. 6, an inner surface 130 of inner wall 122 of ridge 114 can be adjacent to a window rear surface 132 of the rearmost one of window panels 50. An outer surface 132 of outer wall 124 can be sloped such that outer surface 132 tapers away from gasket 54 in a rearward direction from rear surface 136 of window panel assembly 40.

FIG. 7 illustrates a door closed on a corresponding a frame segment assembly 60. When door 36 is closed on frame segment assembly 60, ridge 114 extends rearward part way across gap 140 between rear surface 116 of door 36 and a front surface 142 of frame segment assembly 60. With door 36 closed on frame segment assembly 60, a labyrinthine air passage 144 is formed between interior space 48 and gasket 54.

FIG. 8 is a detail view of the interface between door 36 and frame segment assembly 60 in the vicinity of ridge 114. Labyrinthine air passage 144 is defined by surfaces of ridge 114, frame segment assembly 60, and gasket 54. For example, a first segment 150 of labyrinthine air passage 144 is defined by channel 152 formed by the remaining gap 154 between crown 120 of ridge 114 and front surface 142 of frame segment assembly 60 when door 36 is closed. A second segment 155 of labyrinthine air passage 144 is defined by channel 156 between outer surface 132 of ridge 114 and an inner surface of gasket 54. A third segment 160 of labyrinthine air passage 144 is defined by surfaces of fold 162 of gasket 54. Labyrinthine air passage 144 includes bend 164 between channel 152 and channel 156.

Ridge 114 and labyrinthine air passage 144 may reduce velocity of air between gasket 54 and interior space 48. A reduced air velocity near the gasket may improve thermal performance. Ridge 114 and labyrinthine air passage 144 may also reduce leakage at the mating surfaces between gasket 54 of door 36 and contact plate 44 of frame segment assembly 60.

In the example shown in FIG. 8, the outer surface 132 of ridge 114 generally faces gasket 54. Outer surface 132 tapers away from gasket 54 in the rearward direction. In other implementations, the inner surface can be perpendicular to window panels 50 or can taper at a different angle. In some implementations, outer surface 132 of ridge 114 can be curved and have other surface features, such as grooves or channels.

As illustrated in FIG. 8, a labyrinthine air passage can include through segments, blind segments or combinations thereof. In some implementations, a labyrinthine air passage can include branches into two or more segments.

The distance across gap 154 between ridge 114 and front surface 142 of frame segment assembly 60 when door 36 is closed can vary from one implementation to another. The distance can also vary from installation to installation, or even within a particular installation, because of dimensional tolerances in ridge 114, gasket 54, and other components, how much force is used to close the door, or other physical characteristics and use factors. In some cases, the height of ridge 114 is chosen to ensure a gap between the frame assembly and the ridge in a specified range. In one implementation, gap 154 is between about 2 millimeters and about 4 millimeters. In another implementation, gap 154 is 3 millimeters or less. In certain implementations, a projecting element spans the entire gap between door and frame. In some implementations, a projecting element such as ridge 114 can include slots or holes to control the flow of air or partially define a labyrinthine air passage between a gasket and the interior space of an enclosure. The projecting element for a labyrinthine feature can be made of various materials.

In some implementations of a labyrinthine feature, the projecting element is flexible (such as Vinyl 78 shore A). In other implementations, the projecting element is rigid (such as rigid PVC). In some cases, a flexible material may allow for greater variations in the gap between the rear surface of the door and front surfaces of a frame.

In FIGS. 7 and 8, a labyrinthine air passage is included between one of the lateral edges of a door and a frame assembly along one of the sides of the opening. Nevertheless, in some implementations, a ridge can be included between a door and a mullion. Thus, referring to again to FIG. 3, door 36 includes ridges 114 interior to gasket 54. When door 36 is closed on mullion frame segment 34, a labyrinthine air passage is formed between door 36 and the front surface of mullion frame segment 34.

In addition, ridges for a labyrinthine feature can be provided on frame segments in a horizontal orientation, or in any other orientation FIG. 9 is a vertical cross sectional view of a refrigerated enclosure illustrating ridges that run horizontally on a top/header side and bottom/sill side of the enclosure. Ridges 114 a and 114 b are interior to gasket 54. Ridge 114 a projects inwardly and partially defines a labyrinthine air passage 144 between door 36 and a top frame segment 26. Ridge 114 b projects inwardly and partially defines a labyrinthine air passage 144 a between door 36 and a bottom frame segment 24.

In various implementations described above, a ridge has been illustrated with a quadrilateral cross sectional shape with one tapered side wall. A ridge can have many other cross sectional shapes. As examples, a ridge can be semicircular, arcuate, rectangular, trapezoidal, rounded, or irregular. The surface of a ridge can be smooth, rough, corrugated, wavy, or other contour. In some implementations, ridge is solid in cross section (e.g., with a hollow core) FIGS. 10 through 13 depict examples of alternative ridge shapes for forming a labyrinthine passage. FIG. 10 depicts a ridge 114 having a square cross section with a hollow core. FIG. 11 depicts a ridge 114 having a thin rectangular solid cross section. FIG. 12 depicts a ridge 114 having a rounded hollow cross section. FIG. 13 depicts ridge 114 having a triangular hollow cross section.

FIG. 14 illustrates a rear retaining member that includes a ridge. Rear retaining member 104 includes body 168, rear retaining rim 110, and ridge 114. Body 168 includes gasket engaging portion 169.

In some implementations, a ridge for a labyrinthine feature is included in a component that is separable from other components of the door. For example, as illustrated in FIG. 15, strip 170 can be attachable to rear retaining member 172. Strip 170 or other labyrinth-forming component can be attached to a door in various manners. Examples include a groove and tenon connection, a snap joint, a crimp groove, or an adhesive joint. In one example, a strip is attached to a door by way of pressure-sensitive adhesive tape.

In some implementations, a component for forming a labyrinth feature is retrofitted to a door or frame assembly. The door may be one that is already in inventory, or already installed at retail location. For example, strip 170 shown in FIG. 15 can be attached to a door of a refrigerated enclosure that is already operating and cooling food items.

In certain implementations, a labyrinth feature can project from the frame side of the interface instead of the door side. FIG. 16 illustrates a frame assembly 180 including a ridge 182 that partially extends across an air gap to door 184. Ridge 182 partially defines a labyrinthine air passage 186.

In the implementations described above, only a single labyrinth-forming ridge is included interior to the gasket. An interface between door and frame can, however, include more than one ridge. As an example, a door can include two ridges, spaced apart one another along a rear surface of the door. As another example, the door and frame assembly can each include a ridge extending toward the other. The ridges can be directly opposed to one another or staggered with respect to the exterior edge of the door. In some implementations, one or more staggered ridges of on each of the door and the frame overlap and cooperate to create a winding air path between a gasket and the interior space of an enclosure.

In some implementations, an L-shaped backing member fits on the back and interior faces of an inner member of the frame (the L-shaped member is shown below as a gray shell with light blue core). The backing member includes insulation for reducing thermal transference between the frame and the interior space of the enclosure. The interior leg of the L-shaped backing member may run from the back of the frame to the trailing edge of the door gasket. The contact plate of the frame can extend over the interior leg of the backing member.

FIG. 17 illustrates a frame segment assembly according to an illustrative implementation. Frame segment assembly 60 includes main frame member 202, backing member 204, and contact plate 44. Main frame member 202 includes base 206, middle wall 210, and forward flange 212.

Backing member 204 is coupled to main frame member 202. Interior leg 214 of backing member 204 is against interior wall 216 of main frame member 202. Rear leg 218 of backing member 204 is against rear wall 220 of main frame member 204. Exterior wall 222 of bracket 68 may run along an outer side wall 228 of base 206 and middle wall 210.

Backing member 204 includes bracket 68 and insulating member 230. In the implementation shown in FIG. 16, insulating member 230 has an L-shape with one leg of the insulating member forming part of rear leg 218 of backing member 204, and another leg of the insulating member forming a part of interior leg 214. Over a portion of exterior wall 222, insulating member 231 is disposed between exterior wall 222 of bracket 68 and the middle wall 210 of main frame member 202. Insulating member 224 is provided behind forward flange 212.

The outer end of contact plate 44 is supported by main frame member 202. Contact plate 44 may be held in place with a retaining clip 232 (e.g., a zipper strip or other suitable fastening device). Retaining clip 232 may be coupled to backing member 204 by an engagement feature 234 (e.g., a flange, a notch, a lip, a collar, a groove, etc.) of backing member 204.

Reducing the velocity of air interior to a gasket and the transfer of heat to the cold interior space at the interface of a door and frame may help maintain the temperature of the sealing surface of a contact plate above the dew point of the external environment. This inhibits condensation from forming on the sealing surface of the contact plate. Prevention of condensation on the sealing surface may promote positive engagement and improved thermal seals between contact plates and door gaskets.

FIG. 18 shows a thermal map 240 of results from thermal modeling performed on the door and frame segment assembly of FIGS. 7 and 8. Temperatures ranges are indicated in Fahrenheit degrees. As illustrated by the temperature regions extending along the outer member and to the contact plate, the thermally conductive outer member of the frame assembly readily conducts heat from the external environment to the thermal plate. Thus, main frame member 202 and contact plate 44 may be maintained at a relatively uniform temperature with the external environment. Near the labyrinthine air passage, there is a relatively steep temperature gradient, as indicated by the rapid transition of temperature regions in a short distance from ridge 114 and the interior surface of backing member 204. This steep temperature gradient indicates that the labyrinth feature is preventing heat from the external environment from entering into the inside of the refrigerated enclosure. In this example, a temperature on the exterior surface of the frame may be about 52.6 degrees Fahrenheit.

In certain implementations, a frame includes an elongated edge on the front portion of the frame to increase heat absorption to keep temperature of the frame high enough to avoid condensation.

In certain implementations, a refrigerated enclosure includes a mullion having thickened sidewalls that reduce thermal transference from front to back of the mullion. Thermally insulating material (e.g., foam board) can be placed on the mullion sides. The mullion can include co-extruded portions, one of the co-extruded portions being of a lower density than the other co-extruded portion. The lower density material for the mullion may be, for example, a cellular material or ABS foam. The lower-density co-extruded portion is on the contact-plate side of the mullion. The lower-density co-extruded portion can receive a heater wire and zipper and serves as a thermal break.

In certain implementations, a refrigerated enclosure includes a mullion bracket that serves as a thermal barrier between the mullion and a frame segment to which the mullion is connected. The mullion includes a perimeter flange between the mullion and the frame. The bracket can restrict air from passing between the door frame and the mullion. A rectangular block of the mullion bracket can be inserted into a corresponding opening in the mullion. The block of the mullion bracket can be secured to the mullion by way of opposing fasteners in the lateral walls of the mullion.

In certain implementations, frame members, mullion members, or both, of a refrigerated enclosure have heater wire grooves that position a heater wire in direct contact with contact plate of the frame.

In various implementations described and shown above, a ridge perpendicular to rear surface of the door. A ridge can be at other orientations, such as slanted in an interior direction, slanted in an exterior direction, or curved.

In various implementations described and shown above, a ridge for a labyrinth feature extends across to a backing member of a frame assembly. A ridge can extend across toward other components, however, such as contact plate, a main frame member, or a retaining member.

As used herein, an “air passage” includes any space that allows air to move through or within. In some cases, an air passage can be a through passage that permits air to continuously flow through the passage from one end to another. In other cases, an air passage (or portion thereof) is a blind passage that does not allow for continuous airflow. Air movement in a passage can be caused by pressure differentials, thermal gradients, or otherwise. “Air passage” does not imply that air actually moves within the air passage.

As used herein, in the context of an air passage, a “labyrinthine” air passage includes two or more segments with at least one bend. An air passage having a labyrinthine shape may tend to inhibit flow of air through the passage.

As used herein, a “ridge” includes any element or portion thereof that projects from a surface of a component over at least a portion of the surface. A ridge may be in the form of, for example, a rail, elongated protrusion, rim, bar, or lip. A ridge can project in any direction, including up, down, left, right, sideways, or obliquely.

As used herein, a “member” can be a unitary structure or a combination of two or more members or components.

As used herein, “coupled” includes directly or indirectly connected. Two elements are coupled if they contact one another (e.g., where faces of a frame member and a contact plate are in contact with one another.), but may also be coupled where they do not contact one another.

As used herein, the terms “perpendicular,” “substantially perpendicular,” or “approximately perpendicular” refer to an orientation of two elements (e.g., lines, axes, planes, surfaces, walls, or components) with respect to one and other that forms a ninety degree (perpendicular) angle within acceptable engineering, machining, or measurement tolerances. For example, two surfaces can be considered orthogonal to each other if the angle between the surfaces is within an acceptable tolerance of ninety degrees (e.g., ±1-5 degrees).

It should be noted that the orientation of various elements may differ according to other exemplary embodiments, and that such variations are intended to be encompassed by the present disclosure.

While a number of examples have been described for illustration purposes, the foregoing description is not intended to limit the scope of the invention, which is defined by the scope of the appended claims. There are and will be other examples and modifications within the scope of the following claims. For example, the construction and arrangement of the refrigerated case with thermal door frame as shown in the various exemplary embodiments is illustrative only. Although only a few embodiments of the present inventions have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the description and advantages of the subject matter disclosed herein. For example, elements shown as integrally formed may be constructed of multiple parts or elements, the position of elements may be reversed or otherwise varied, and the nature or number of discrete elements or positions may be altered or varied. Accordingly, all such modifications are intended to be included within the scope of the present invention as defined in the appended claims. Other substitutions, modifications, changes and omissions may be made in the design, operating conditions and arrangement of the various exemplary embodiments without departing from the scope of the present inventions. 

What is claimed is:
 1. A temperature-controlled enclosure for displaying cold items, comprising: a body comprising a front opening and defining an interior space of the enclosure; a frame assembly coupled in the front opening of the body; and one or more doors coupled to the frame assembly, wherein at least one of the doors comprises: one or more window panels; a housing assembly configured to hold the one or more window panels along the exterior edges of the one or more window panels, the housing assembly comprising a rear surface and defining a perimeter; a gasket coupled to the housing assembly on the rear surface of the housing assembly along the perimeter, wherein the gasket is configured to form a seal between the frame assembly and the door when the door is closed; and a ridge projecting from the rear surface of the housing assembly between at least a portion of the gasket and the interior space of the enclosure, wherein the ridge extends across at least a portion of an air gap between the rear surface of the housing assembly and a front surface of the frame assembly.
 2. The temperature-controlled enclosure of claim 1, wherein the ridge at least partially defines an air passage between the interior space and the gasket when the door is closed, and wherein the ridge is configured to inhibit air flow between the gasket and the interior space of the enclosure.
 3. The temperature-controlled enclosure of claim 1, wherein the ridge at least partially defines a labyrinthine air passage between the interior space and at least one inner surface of the gasket when the door is closed.
 4. The temperature-controlled enclosure of claim 3, wherein the labyrinthine air passage comprises: a first segment between the ridge and a front surface of the frame assembly, and a second segment between an outer surface of the ridge and an inner surface of the gasket.
 5. The temperature-controlled enclosure of claim 1, wherein the labyrinthine air passage is configured to inhibit air leakage between the gasket and a contact plate of the frame assembly.
 6. The temperature-controlled enclosure of claim 1, wherein the labyrinthine air passage is configured to inhibit heat transfer between ambient air around the temperature-controlled storage device and the interior space of the enclosure.
 7. The temperature-controlled enclosure of claim 1, wherein the labyrinthine air passage is configured to inhibit condensation on the door or the frame assembly.
 8. The temperature-controlled enclosure of claim 1, wherein the housing assembly comprises a window panel retaining member, wherein the ridge is formed in the window panel retaining member.
 9. The temperature-controlled enclosure of claim 1, wherein the ridge comprises a flexible material.
 10. The temperature-controlled enclosure of claim 1, wherein the ridge comprises a rigid material.
 11. The temperature-controlled enclosure of claim 1, wherein the ridge comprises a hollow core.
 12. The temperature-controlled enclosure of claim 1, wherein the ridge comprises, in cross section, a rectangular shape.
 13. The temperature-controlled enclosure of claim 1, wherein the ridge comprises, in cross section, a polygonal shape.
 14. The temperature-controlled enclosure of claim 1, wherein the ridge comprises at least one rounded external surface.
 15. The temperature-controlled enclosure of claim 1, wherein the air gap between the ridge and the front surface of the frame assembly is about 3 millimeters or less.
 16. The temperature-controlled enclosure of claim 1, further comprising one or more additional ridges projecting from the rear surface of the housing assembly, wherein at least one of the additional ridges at least partially defines the air passage between the interior space and the gasket when the door is closed, wherein the at least one additional ridge is configured to inhibit air flow between the gasket and the interior space of the enclosure.
 17. The temperature-controlled enclosure of claim 1, wherein at least a portion of the ridge runs along the gasket around the perimeter of the housing assembly.
 18. The temperature-controlled enclosure of claim 1, wherein at least a portion of the ridge runs along the gasket on the top edge or the bottom edge of the door.
 19. The temperature-controlled enclosure of claim 1, wherein at least a portion of the ridge runs along the gasket on at least one of the side edges of the door.
 20. The temperature-controlled enclosure of claim 1, wherein at least a portion of the ridge runs along the gasket on a hinged side of the door.
 21. The temperature-controlled enclosure of claim 1, wherein at least a portion of the ridge runs along the gasket on a handle side of the door.
 22. The temperature-controlled enclosure of claim 1, wherein at least a portion of the ridge is between the gasket and an exposed edge of at least one of the window panels.
 23. The temperature-controlled enclosure of claim 1, wherein the frame assembly comprises one or more mullions coupled between a top frame segment and a bottom frame segment.
 24. The temperature-controlled enclosure of claim 1, wherein at least a portion of the ridge is configured to extend across at least a portion of an air gap between the rear surface of the housing assembly and a front surface of the mullion.
 25. The temperature-controlled enclosure of claim 1, wherein the frame assembly comprises a contact plate, wherein at least one segment of an air passage between the gasket and the interior space is at least partially defined by a gap between the ridge and a front surface of the contact plate.
 26. The temperature-controlled enclosure of claim 1, wherein the frame assembly comprises a main frame member and a backing member coupled to the main frame member, wherein the backing member comprises a leg on the inner side of the main frame member, and wherein at least one segment of an air passage between the gasket and the interior space is at least partially defined by a gap between the ridge and a front surface of the leg of the backing member.
 27. A temperature-controlled enclosure for displaying cold items, comprising: a body comprising a front opening and defining an interior space; a frame assembly coupled in the front opening of the body; and one or more doors coupled to the frame assembly, wherein at least one of the doors comprises: one or more window panels; a housing assembly configured to hold the one or more window panels along the exterior edges of the one or more window panels, the housing assembly comprising a rear surface and defining a perimeter; a gasket coupled to the housing assembly on the rear surface of the housing assembly along the perimeter, wherein the gasket is configured to form a seal between the frame assembly and the door when the door is closed; and a ridge extending across at least a portion of an air gap between the rear surface of the housing assembly and a front surface of the frame assembly, wherein the ridge is configured to inhibit air flow between the gasket and the interior space of the enclosure.
 28. The temperature controlled enclosure of claim 27, wherein the ridge projects from the rear surface of the housing assembly between the gasket and the interior space of the enclosure.
 29. The temperature controlled enclosure of claim 27, wherein the ridge projects from the front surface of the frame assembly between the gasket and the interior space of the enclosure.
 30. A door for a temperature controlled enclosure for displaying cold items, comprising: one or more window panels; a housing assembly configured to hold the one or more window panels along the exterior edges of the one or more window panels, the housing assembly comprising a rear surface and defining a perimeter; a gasket coupled to the housing assembly on the rear surface of the housing assembly along the perimeter, wherein the gasket is configured to form a seal between the frame assembly and the door when the door is closed; and a ridge projecting from the rear surface of the housing assembly interior to the gasket, wherein, when the door is closed on a frame assembly mounted in an enclosure of the temperature controlled storage device, the ridge is configured to extend across at least a portion of an air gap between the rear surface of the housing assembly and a front surface of the frame assembly.
 31. A method of improving thermal performance of a refrigerated enclosure, comprising: providing a frame assembly for holding a door for the refrigerated enclosure; and providing a ridge on a rear surface of a door of the enclosure interior to a gasket of the door, wherein, when the frame assembly and door are installed and the door is closed, a labyrinthine air passage is created between the door and the frame assembly, wherein the labyrinthine air passage is at least partially defined by the ridge, and wherein the ridge is configured to inhibit air flow between the gasket and the interior space of the enclosure. 